1. Field of the Invention
The invention relates in general to a lens module and an electronic device using the same, and more particularly to a lens module with a lever driving a lens and an electronic device using the same.
2. Description of the Related Art
Lenses are used for capturing images. Light is focused on a photosensitive surface of an image sensor by the lens to form an image on the photosensitive surface. The lens may be composed of several to dozens of concave lenses and convex lenses. The concave lenses and the convex lenses produce a focal length. As to a zoom lens, the focal length of the zoom lens is adjustable by changing a distance between the concave lenses and the convex lenses, and the image on the photosensitive surface of the image sensor is enlarged or reduced by the different focal length. It is very convenient for users to use the lens in various situations. Therefore, the zoom lenses are widely applied to all kinds of electronic devices with camera function.
Please referring to FIG. 1, a conventional zoom lens is illustrated in FIG. 1. The conventional zoom lens 10 includes a cam tube 100, a lens 120 and a lens tube 160. Light passes through the lens 120 and the lens tube 160 to reach an image sensor. A spiral groove 101 is formed on the cam tube 100 for connecting the cam tube 100 with the lens tube 160. Due to the characteristic of the spiral movement, when the cam tube 100 rotates, the cam tube 100 moves upwards or downwards along the lens tube 160. The lens 120 is disposed inside the cam tube 100. Therefore, the position of the lens 120 is adjusted by changing the related locations of the cam tube 100 and the lens tube 160. The conventional zoom lens 10 further includes a sliding bump 140. The sliding bump 140 is coupled with the lens 120. A strip groove 162 is formed on the lens tube 160. The sliding bump 140 located in the strip groove 162 allows the lens 120 to slide along the strip groove 162. Therefore, when the cam tube 100 rotates, the sliding bump 140 and the strip groove 162 restrain the movement of the lens 120. That is, the lens 120 only moves upwards or downwards. The lens 120 does not sway when the focal length is changed, and the image quality is not affected.
However, it is difficult to manufacture the spiral groove 101 because the spiral groove 101 requires high accuracy in the manufacturing process. Therefore, the manufacturing cost of the cam tube 100 is relatively high. After the cam tube 100 is manufactured, it is also hard to check the dimension of the cam tube 100 such that the inspection cost is high as well. Additionally, when defective cam tubes are processed in the following manufacturing process, it results in defective semi-products, which increase the manufacturing cost. Therefore, it is very important to resolve the above problems.